Why are you removing support for Java 6 and 7?
Support is being removed because Java 6 and 7 are old versions that are no longer being updated by Oracle. We also want Minecraft to run faster.

What is Java?Java is the programming language that Minecraft is written in. Any program written in Java requires that you have it installed before using that program.

How can I update to the newest version of Java?
If you do not have automatic Java updates enabled (or if you need to download Java for the first time), you can obtain the newest version by visiting http://java.com/download.

You also get the correct version of Java when you download the Minecraft game launcher from Minecraft.net/download.